This is a renewal application for a training program, now in its 9 year, designed to attract and train both predoctoral and postdoctoral investigators in basic investigation of cardiovascular and pulmonary biology, with the goal of preparing these scientists for research careers in these fields. Our goal is to continue to draw upon our excellent faculty to train new scientists for academic research careers in cardiovascular and pulmonary biology. The objectives are: (i) to provide an extended period of full-time, protected investigative training in a clinical or bench laboratory with an accomplished scientific mentor, (ii) to correlate basic developmental biology and physiology with clinically relevant cardiovascular and pulmonary defects, (iii) to provide financial support and facilities for laboratory investigation, and (iv) to guide the trainees' development so that after completion of training successful competition for independent funding is likely. The need for a training program in cardiovascular and pulmonary development, especially of physician- scientists interested in childhood diseases, is based upon clear evidence of a small, national pool of such individuals currently as faculty or trainees. Currently, few pediatric cardiology or pulmonary fellowship programs in American medical centers provide adequate research training in this area of research, either at the bench or in structured clinical investigation. Our program is designed to address this need from two important perspectives: 1) To allow pediatric and other clinical fellows with an interest in basic research to develop research competence and career training. 2) To attract and train talented basic scientists to study mechanism related to childhood diseases. With the objectives of the program in mind, we have adopted a training curriculum for 4 postdoctoral (1 MD - PGY-4 and 3 PhD -1 PGY-1 and 2 PGY-3) and 2 predoctoral fellows with an uninterrupted 2-4 year block of full-time investigation. This is combined with an integrated and multidisciplinary set of didactic seminars, journal clubs and formal courses to provide education in many aspects of cardiopulmonary development and disease. The program is highly integrative with current pediatric cardiology, pediatric pulmonary, genetics, pediatric critical care, neonatology, cardiovascular medicine fellowship training programs and with the graduate and MSTP programs. Washington University School of Medicine and the departments of the participating faculty provide an excellent and proven environment for scientific training in the areas of emphasis. Congenital heart and vascular defects and abnormalities in lung formation and function remain among the most common causes of death in infancy and early childhood. The purpose of this training program is to attract and train young scientists to study mechanisms related to childhood diseases.